The present invention relates to display devices where information can be browsed. In particular, the present invention relates to a novel and improved method and system for browsing information with hand-held devices with a display device.
Various electronic mobile devices, e.g. mobile phones, computers, Personal Digital Assistants (PDAs), comprise displays. The transfer of the information to be viewed on the display is executed at least partially by a processor. A device typically comprises also a keypad with which the user of the device enters various commands. There are also touch-sensitive displays (touch screens). There a separate keypad is not needed. A device is controlled by touching the touch screen.
The display of a mobile device is capable of showing only limited amount of information at a time. Because of the size of the display, e.g. a large image must be viewed part by part. In order to view such an image, the user of the device controls the display, e.g. by scrolling the display with a mouse etc.
Devices equipped with a display have different kinds of user interfaces with which the user interacts with the device. There are graphical user interfaces and speech controlled user interfaces. A graphical user interface can be controlled with various control devices including, for example, keypad, touch screen, different kinds of cursor controlling methods, etc.
There are, however, drawbacks in the prior-art devices in the usability of the device, especially in the browsing of information with the device. When the information to be viewed on the display must be viewed by parts, it is difficult and slow to browse the whole information part by part. It is, for example, difficult to display a wide panorama picture on the display, while at the same time quickly and easily browsing the picture.
For the user of a mobile hand-held device it is difficult to perceive visual entireties that can not be displayed at a time on the display. Therefore the browsing of the information should be carried out as naturally and logically as possible. A user of a mobile hand-held device must be able to learn and use the device easily and efficiently.
From prior-art solutions it is known to use location detectors for browsing information with a device. Reference publication WO 9918495 (Telefonaktiebolaget LM Ericsson) describes a method where the display device is moved essentially in the plane of the display device, whereby different parts of a complete screen image are shown on said display device. When the display device is moved essentially in a direction perpendicular to the plane of the display device, the magnification of the screen image changes. The movement in the plane is a bit problematic. In the plane movement the necessary movements may be quite remarkable/large, and it may be difficult to maintain the display device in a proper position for reading or browsing.
Another prior-art solution is to use tilt detectors for moving, or to be more specific, for scrolling the view on the display device. One solution of this kind is described in WO 9814863 (Philips). When the screen image is moved by scrolling (tilting the display device), the result is better than in moving the display device in the plane of the display device, as described above. However, to move the screen image fluently and to return from some point to the initial point of browsing is difficult because controlling a discontinuous motion requires continuous and precise handling of the display device. The controlling of the scrolling movement can be compared to a movement of a ball on a plane surface by tilting the plane. In order to stop the rolling of the ball, the plane surface must be perpendicular against the gravity of the earth. In other words, the control of the movements and usability are not at an acceptable level so that the use of such a device would be natural and logical.
There are also various kinds of motion and/or location controlled display devices used in, e.g. in virtual helmets. There the display device focuses like a virtual camera. The display device displays an object to which the device (camera) points in the modelled virtual environment. To use a virtual camera model in a hand-held device is not so straightforward because displaying peripheries of a large screen image results in a disadvantageous viewing angle. Therefore, the adjustment and zooming of a display image must be implemented in a most natural and logical manner. In prior-art solutions the browsing of information on the display device is slow and awkward because the solutions are based on artificial logic.